View Single Post
  #20 (permalink)  
Old 2nd November 2007, 13:57
john john is offline
Senior Member
 
Join Date: Nov 2007
Location: Manchester
Posts: 383
Default

Now that it is dark on the way home and being inspired by this thread I thought it was time to add some more lighting to my bike.

I'd been looking at LED's for a while but my criteria were:

- I didn't want to spend a lot of money
- I didn't want it to take a lot of time to put together

Taking some of the ideas from this thread, I went home last night and started playing with an MR16 12V LED bulb I got from ULTIMASTORE - Energy Saving Lamps, LED'S, LED recently. I don't know exactly what is in these but they seem to work happily on 12V AC or DC. I measured the current at about 35mA when connected to a 12V battery and then connected it in series with 820 ohm resistor to connect it to my 36V supply. (actually I used 4 820 resistors in series/parallel - if you know what I mean - in order to handle the power )

I cut a piece of galvanized steel and drilled two holes in it. One for the mounting bolt and a larger one for the bulb. This would then be mounted in place of the front reflector. I used a reamer to make the bulb hole big enough and fixed it in with silicone. Leave overnight to dry and connect the wires to the battery. Bob's your uncle. A really bright light for about half a hour's work and a few quid.

I think it should be OK in the rain as the bulb appears to be totally encased in glass.

The bulb consumes about 0.5 w and the resistors waste about 1W. I'm not too happy about the waste but it's not going to affect my range by more than a few yards so what the heck.
Reply With Quote